GR740-UM-DS, Nov 2017, Version 1.7
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GR740
15.2.3 Extended PCI Configuration Space
This section describes the first item in the list of capabilities implemented in the Extended PCI Con-
figuration Space. This capability is core specific and contains the PCI to AMBA address mapping and
the option to change endianess of the PCI bus.
Table 256.
GRPCI2: Internal capabilities of the Extended PCI Configuration Space
PCI address offset (with the Capabilities
pointer as base)
Register
0x00
Length, Next Pointer, ID
0x04 - 0x18
PCI BAR to AHB address mapping
0x1C
Extended PCI Configuration Space to AHB address mapping
0x20
AHB IO base address and PCI bus config (endianess switch)
0x24 - 0x38
PCI BAR size and prefetch
0x3C
AHB master prefetch burst limit
Table 257.
0x00 - Length, Next pointer and ID
31
24 23
16 15
8
7
0
RESERVED
Length
Next Pointer
Capability ID
0
0x40
0x00
0x09
r
r
r
r
31: 24
RESERVED
23: 16
Length - Returns 0x40.
15: 8
Next Pointer - Pointer to the next item in the list of capabilites. Set to 0x00
7: 0
Capability ID - Returns 0x09 indicating Vendor Specific.
Table 258.
0x04-0x18 - PCI BAR to AHB address mapping register
31
0
PCI BAR to AHB address mapping
0
rw
31: 0
PCI BAR to AHB address mapping - 32-bit mapping register for each PCI BAR. Translate an access
to a PCI BAR to a AHB base address. The size of the BAR determine how many bits (starting form
bit 31) are implemented. Bits non implemented returns zero
Table 259.
0x1C - Extended PCI Configuration Space to AHB address mapping register
31
8
7
0
Extended PCI Configuration Space to AHB address mapping
RESERVED
0
0
rw
r
31: 8
Extended PCI Configuration Space to AHB address mapping
- Translates an access to the Extended PCI Con-
figuration Space (excluding the address range for the internal register located in this configuration
space) to a AHB address.
7: 0
RESERVED